New design-seeking advice

[MrGneissGuy]

After I built the StegoSoarus for my daughter, she has apparently come to the conclusion that whatever her mind thinks up I can make into a rocket. Now she's asking for a dog. Playing in Open Rocket today, I came up with something that I think will work. I designed it with the Big Bertha nose cone and body tube. It turned out with 0.79 cal with a C motor, adding an ounce of nose weight makes it 1.78 cal. I put the Open Rocket images into paint.net and put together the rough finishing. First pic top down, second is from the side, and third is from the bottom. Fourth picture is the inspiration. My question is regarding the tail. How am I going to strengthen it for the landing? Would it be ok to use craft ply for the tail and balsa for the "cape"? Would papering it work? Is there a way to rig up the parachute so that it comes down flat? Or just resign myself to making repairs after every other launch?

[Rex R]

papering fins etc. works for me . horizontal recovery works, but can be hard on anyting that is on the underside. if you have grass/weeds that helps alot. I used 100# kevlar thread, but I think that 50# 'spider wire' would have worked too(I use a baffle in my intercept missile).
rex

[Micromeister]

Being the crazy Odd-Roc'er that I am.
Looking at Under Dog I'd likely make him sort of like an SR-71 body wrap over body tube, with Balsa inner wing stiffeners papered as Rex R suggested. I'd also widen the tail making it either curl more or perhaps trail out behind a bit..you might even consider adding the tail to a clear Lexan fin piece for a bit more aero
adding a teather to lower the model horizontally might be more trouble then it's worth. as it would likely fowl on the tail anyway. I'm thinking that clear fin with tail added could be a good alternative?
Very Kewl dream.. Can't wait to see the finished product

[Micromeister]

papering fins etc. works for me . horizontal recovery works, but can be hard on anyting that is on the underside. if you have grass/weeds that helps alot. I used 100# kevlar thread, but I think that 50# 'spider wire' would have worked too(I use a baffle in my intercept missile).
rex

Rex;
Spider Wire is GREAT fishing line but not worth a hoot near any kind of heat. The stuff just doesn't like to even get close to warm things let along ejection charges.

[JPVegh]

If you rigged it as a rear ejection model with external shock cord and streamer recovery you might be able to get the effect your looking for. It might be a PITA to get right but it would be fun doing the testing.

Since you never see underdogs tail in any of the cartoons I'm not sure that it even belongs in the design. When he is flying you do see his feet under the cape angled out from one another. Perhaps feet fins?

However you figure this one out I gotta say that you are one creative dude.

[MrGneissGuy]

Since you never see underdogs tail in any of the cartoons I'm not sure that it even belongs in the design. When he is flying you do see his feet under the cape angled out from one another. Perhaps feet fins?

That is not only true, but very likely solves my concerns about a thin, easily broken tail. Kind of long, semi-elliptical feet on the underside. Move the "cape" fins to the top...thank you!

I've also been thinking of what micro said about the body wrap, but with a twist. I'm trying to decide if I can take card stock and bend it (not fold it) onto the "cape" balsa to make it appear more cloth-like and not flat.

Very rough 30 second sketch showing what I mean...I knew there was a reason I posted this in here. Thanks all! Now...to pick up a Big Bertha and some balsa...

[MrGneissGuy]

Well, I got around to buying the parts and actually got started on this thing. I got the motor mount put together and the "cape" cut out in two sections and glued together. Tonight the "feet" get cut out, the motor mount installed, and then I'm going to experiment with putting some "folds" in the cape with card stock.

[modeltrains]

This is going to be an interesting rocket.

[luke strawwalker]

Yeah, I'd go with rear eject...

Course if you're not doing the tail, you can go with the standard forward eject...

Later! OL JR

[[POW]Eagle159]

Making it a glider would be very cool... a flying super dog!!!!!!

[jeffgeraci]

STOP! The head is WAY too small! The head is the prominent feature, so it should be OVERSIZED. With a C motor, or even a D or E, you can use a larger and oddly shaped nose cone, and it will fly fine. I did a cube nosecone for sponge bob and it flew great.
Please consider carving the head out of a block of balsa, making it the actual shape of underdog's head (not the shape of a cone!), and make it big. Go for it

[MrGneissGuy]

STOP! The head is WAY too small! The head is the prominent feature, so it should be OVERSIZED. With a C motor, or even a D or E, you can use a larger and oddly shaped nose cone, and it will fly fine. I did a cube nosecone for sponge bob and it flew great.
Please consider carving the head out of a block of balsa, making it the actual shape of underdog's head (not the shape of a cone!), and make it big. Go for it

I am no where near the artist you are and while I have made a fairly good drawing on the Big Bertha cone (black Sharpie and color pencils covered with clear coat), I have very little confidence in my ability to do any kind of carving.

Though you make a very valid point about the size of his head. While I'm happy with individual components in the build, when it is all together it doesn't look as nice. Basically, it's a scale thing. With trying to make sure it stands a better chance of being stable, I've compromised some on the look. If I were going strictly for looks, I'd shorten it quite a bit, make the cape wider, the feet a little smaller, etc. But I had concerns about stability and was having a heck of a time getting the cape right in Open Rocket to get a good simulation, so I'm being conservative.

But after thinking about your post some, an oversized head would improve the overall look greatly and I have a plan. I'm going to go ahead and finish it as is and get a test flight or two in, but at the same time work on molding a different head out of clay. If I can get something that looks good, I'll duplicate the process over the current nose cone using Crayola Model Magic (or something similar) and epoxy it into place. That's a pretty big "if" though.

I actually have the rocket assembled and primed, with a little bit of white on the chest so I can mask off the "U". I ended up papering the fins to make them stronger. I'll try to remember to take and post some pictures later.

[jeffgeraci]

The head isn't do or die: it's gonna look great no matter what size, and let's face it- kids could care less, they'l love it regardless. Smart to paper the fins after all that painstaking work shaping them! Hope to see more pics soon, it's gonna be a keeper

[MrGneissGuy]

Some pics of it in its current form. I have the white paint on, the "U" masked, and the cape painted blue. Next is masking the cape and painting the body and feet red. It's kind of a Plastic Man version of Underdog...stretched tall and skinny.

The third pic is the nose cone with the face I drew on it. My daughter (the one who wanted a dog rocket) said she thought my drawing was even cuter than the original. So I've got a bit of a seal of approval so far.

[jeffgeraci]

Not an artist?! Dry that one out and you can fertilize the lawn. That's a damn good painting on the nosecone, and on a ROUNDED surface no less! Very keeeeeeewwwl!

[MrGneissGuy]

All done except clear coat and a test flight. I wish I had made the "U" better, of all the difficult parts to make, I'm least happy with the simple bubble letter "U" .

Even if it's all stretched and out of proportion, hopefully it's still pretty obvious who it's supposed to be, and hopefully he'll fly well. I'm thinking first flight on a B6-2. I have a feeling it's going to need a short delay.

[Scotty Dog]

All done except clear coat and a test flight. I wish I had made the "U" better, of all the difficult parts to make, I'm least happy with the simple bubble letter "U" .

Even if it's all stretched and out of proportion, hopefully it's still pretty obvious who it's supposed to be, and hopefully he'll fly well. I'm thinking first flight on a B6-2. I have a feeling it's going to need a short delay.

......job on that rocket. My Underdog(Big Daddy) has yet to take to the skies. Been windy everyday for what seems like forever. I got to much coin and time in it to lose it on its first flight.Anywhoo- Again, great job.

[MrGneissGuy]

......job on that rocket. My Underdog(Big Daddy) has yet to take to the skies. Been windy everyday for what seems like forever. I got to much coin and time in it to lose it on its first flight.Anywhoo- Again, great job.

Actually, your Underdog Big Daddy is what gave me the idea. When that girl said she wanted a dog rocket, I was clueless how I was going to make something that looks like a dog fly...until I saw those big elliptical feet and cape in your build thread (though I still don't know if it'll fly).

I was wondering if you ever got it in the air. Two evenings ago was perfect for a quick low flight out back. But the paint was still wet.

[Scotty Dog]

I was wondering if you ever got it in the air. Two evenings ago was perfect for a quick low flight out back. But the paint was still wet.

I had it loaded (Daddy)and at the field when I flew my scratchers the other eve.The wind was blowing into the corn and the higher you got the worse it was.So,I chickened out and didnt send it. Didnt want to turn it into a CornDog Anywhoo- I got a vinyl decal left over from my build. Didnt know if you would be interested in it. I think it may be a little big, but whatever. I dont have it in front of me so Ill guess its around 4-5 long 11/2 wide. Its just the lettering ,not the yella back ground. Let me know and Ill dig it out and get true size if you are interested in it. Its FREE!

[MrGneissGuy]

We had a little bit of calm this evening, and my daughter wanted to give it a try so we loaded him up. The first time I stepped out, it was a bit breezy. Not bad at all, but out back, there are a couple of trees and the wind was blowing straight in their direction. So I got nervous and went with a B4-2 instead of the planned B6-2. You know what they say about going with your first instinct?

He flew stable, low and slow off the pad. But a little too low and those two seconds seemed to take an hour. But the ejection charge went off in just enough time to slow it down some and believe it or not, there is no damage. Good thing I papered the fins.

Scotty Dog, thank you very much for the offer, but I can't think of where that vinyl would go well on the rocket. I'll look at it some more and let you know, though.




http://www.youtube.com/watch?v=ZFEbiewlef4

[Scotty Dog]

Yup, buy the sounds it did seem like an hour delay. I hear ya on the decal.Pretty much my thoughts,but I figured Ild throw it out there anywhoo.

[JPVegh]

That is a very cool rocket! You sir are an artist and a very creative one at that.

Looking at the Video I don't think I would fly that pup on anything less than a C6-3.

Great Job man!

[jeffgeraci]

I really like the gasp as the chute opens last second... that was what?- about a "9" on the 'pucker-factor'? lol

[MrGneissGuy]

Underdog may be retired. A couple of weeks back during a club launch he went up on a C6. There was a bit too much wobble to him. It kind of looked like he was wagging his tail the whole way up. I didn't see any wobble in the first launch on the B motor but I'm guessing his cape is a little too flexible and caused the wobble wih the higher velocity of the C motor. Good deployment and recovered undamaged though.

[thereaper87]

When you get the chance, I would think another launch on a B6-4 would look and fly really well. A C6-(), might get him up there a bit, and from the video, you have quite a few trees around